You access the module settings by navigating to Configuration > APSIS One in your Drupal environment.
There are two settings available for configuration here.
APSIS One segmentation view mode
This setting lets you choose whether you want your segments displayed as a list of checkboxes or as a searchable dropdown.
If you have more than 5 segments APSIS Recommends that you choose the dropdown, and if you have 5 or less, APSIS Recommends that you choose the checkboxes.
This is purely an aesthetic option within Drupal and you can change it whenever you want.
If this box is checked, all segment evaluations are cached as per the cache settings in your Drupal environment. If left unchecked, segment evaluations are not cached. This leads to higher precision but more outgoing API calls from the Sitecore environment.